The present disclosure generally relates to LED drivers, and more particularly, to an LED driver with linearly controlled dimming.
As a result of continuous technological advances that have brought about remarkable performance improvements, light-emitting diodes (LEDs) are increasingly finding applications in traffic lights, automobiles, general-purpose lighting, and liquid-crystal-display (LCD) backlighting. As solid state light sources, LED lighting is poised to replace existing lighting sources such as incandescent and fluorescent lamps in the future since LEDs do not contain mercury, exhibit fast turn-on and dimmability, and long life-time, and require low maintenance. Compared to fluorescent lamps, LEDs can be more easily dimmed either by linear dimming or PWM (pulse-width modulated) dimming.
A light-emitting diode (LED) is a semiconductor device that emits light when its p-n junction is forward biased. While the color of the emitted light primarily depends on the composition of the material used, its brightness is directly related to the level of current flowing through the junction. Therefore, it is typically desirable for an LED driver circuit to generate a constant current.